The internal workings of all three leagues are identical; they differ only in the kind of players that are allowed.

Human players may play in the HCL and ACL at the same time. However, they should always remember that the use of chess engines is strictly forbidden in the HCL. The records of players playing in both human leagues are kept completely separate. Every player has a playing class and a rating in HCL and a completely independent class and rating in ACL. Games played in the HCL do not influence your records in the ACL and vice versa.

Human Chess League (HCL)

The HCL is for human players only. In these tournaments the use of chess computers and chess engines (except database software) are strictly forbidden. This means that you might use chess databases like ChessBase (light) to help you in the opening phase of the games. This is similar to the use of opening books (that are allowed, too). But it is not allowed to use chess engines of any kind to calculate moves - not even for a final "check up".

Advanced Chess League (ACL)

In the ACL human players are encouraged to use chess software of any kind. However, the players should not blindly trust their silicon partners, but decide with each move if they take the proposal of their chess program(s) or follow their own thinking.

This kind of playing chess has been made popular by chess champion Garry Kasparov.

Note: If you register as a human player you are allowed to play tournaments in the HCL and in the ACL as well. However, you should always behave according to the rules of each league. Never let chess engines help you in HCL tournaments!

Computer Chess League (CCL)

The CCL is for computer programs only. Especially self-written software may be put to the test of slow time control play.